Which DSLR camera to choose for gigapixel photography

In search for which camera to choose for gigapixels: Crop with less gigapixels? or Full Frame with more gigapixels? I made a simple comparison table where pixels per degree are calculated:

crop factor

angle in degrees

300mm 1.5x (APC Nikon)

1.5

3.1

300mm 1.6x (APC Canon)

1.6

2.9

300mm 1x (FF)

1

4.6

Assume, we have 300mm lens and portrait orientation of camera:

Camera

Megapixels

image width in pixels

crop

angle in degrees

pixels in 1 degree

Number of images required to cover 360 (with 0 overlap)

Equatorial 360 panorama’s width in pixels

Nikon D7200

24

4000

1.5

3.1

1290

116

464516

Canon 750d

24

4000

1.6

2.9

1379

124

496552

Canon 7d mkII

24

3648

1.6

2.9

1258

124

452855

Canon 5d mkIII

22

3840

1

4.6

835

78

300522

Nikon d810

36

4912

1

4.6

1068

78

384417

Canon 5ds r

50

5792

1

4.6

1259

78

453287

These number doesn’t take into account diffraction which can be a practical issue.

Sony APS-C cameras with 24Mpix should be treated similar to Nikon D7200.
More pixels in degree – better. FF is better than APC-S (requires less images). So for me the winner is Canon 5ds r – it allows to achieve almost the same pixel density as other cameras but you can get the same gigapixel with less images – which will mean less overlaps, less space on a card and computer required, faster shooting/stitching..